1842, "state of being fibrillar" (that is, "arranged in fibrils"), noun of action from fibrillate (v.). Especially "a quavering in the fibrils of the muscles of the heart" causing irregular beating (1882).

1670s, "clasp, buckle, brooch," from Latin fibula "clasp, brooch; bolt, peg, pin," related to figere "to drive in, insert, fasten" (see fix (v.)). In reference to brooches, the modern English word mostly is used in archaeology. As "smaller bone in the lower leg" from 1706, from a Latin loan-translation of Greek perone "small bone in the lower leg," originally "clasp, brooch; anything pointed for piercing or pinning;" the bone was so called because it resembles a clasp such as that found in a modern safety pin. Related: Fibular.

Sense of "changeable, inconstant, unstable" is from c. 1300 (especially of Fortune and women). Related: Fickleness. Fickly (c. 1300) is rare or obsolete. Also with a verb form in Middle English, fikelen "to deceive, flatter," later "to puzzle, perplex," which survived long enough in Northern dialects to get into Scott's novels. Fikel-tonge (late 14c.) was an allegorical or character name for "one who speaks falsehoods."

1620s, "molded or formed by art," from Latin fictilis "made of clay, earthen," from fictio "a fashioning" (see fiction). From 1670s as "capable of being molded." From 1854 as "pertaining to pottery." Related: Fictility.

early 15c., ficcioun, "that which is invented or imagined in the mind," from Old French ficcion "dissimulation, ruse; invention, fabrication" (13c.) and directly from Latin fictionem (nominative fictio) "a fashioning or feigning," noun of action from past participle stem of fingere "to shape, form, devise, feign," originally "to knead, form out of clay," from PIE *dheigh- "to build, form, knead" (source also of Old English dag "dough;" see dough).

Meaning "prose works (not dramatic) of the imagination" is from 1590s, at first often including plays and poems. Narrower sense of "the part of literature comprising novels and short stories based on imagined scenes or characters" is by early 19c. The legal sense (fiction of law) is from 1580s. A writer of fiction could be a fictionist (1827). The related Latin words included the literal notion "worked by hand," as well as the figurative senses of "invented in the mind; artificial, not natural": Latin fictilis "made of clay, earthen;" fictor "molder, sculptor" (also borrowed 17c. in English), but also of Ulysses as "master of deceit;" fictum "a deception, falsehood; fiction."

"stringed musical instrument, violin," late 14c., fedele, fydyll, fidel, earlier fithele, from Old English fiðele "fiddle," which is related to Old Norse fiðla, Middle Dutch vedele, Dutch vedel, Old High German fidula, German Fiedel "a fiddle;" all of uncertain origin.

The usual suggestion, based on resemblance in sound and sense, is that it is from Medieval Latin vitula "stringed instrument" (source of Old French viole, Italian viola), which perhaps is related to Latin vitularia "celebrate joyfully," from Vitula, Roman goddess of joy and victory, who probably, like her name, originated among the Sabines [Klein, Barnhart]. Unless the Medieval Latin word is from the Germanic ones.

FIDDLE, n. An instrument to tickle human ears by friction of a horse's tail on the entrails of a cat. [Ambrose Bierce, "The Cynic's Word Book," 1906]

Fiddle has been relegated to colloquial usage by its more proper cousin, violin, a process encouraged by phraseology such as fiddlesticks (1620s), contemptuous nonsense word fiddle-de-dee (1784), and fiddle-faddle. Century Dictionary reports that fiddle "in popular use carries with it a suggestion of contempt and ridicule." Fit as a fiddle is from 1610s.

late 14c., "play upon a fiddle," from fiddle (n.); the figurative sense of "to act nervously, make idle movements, move the hands or something held in them in an idle, ineffective way" is from 1520s. Related: Fiddled; fiddling.

also fiddlehead, "one with a head as hollow as a fiddle," 1854 (fiddleheaded), from fiddle (n.) + head (n.). As a name for young fern fronds, from 1877, from resemblance to a violin's scroll. Earliest use is nautical, "carved ornamental work at the bow of a ship in the form of a scroll or volute" (1799).

There are three kinds of heads,--1st The Figure-head is one on which is placed the figure of a man, woman, or the like, &c.; 2d, The Billet-head, or Scroll-head is one finished with two scrolls or volutes ...; and 3d, the Fiddle-head, which is finished with only one scroll or volute, having the spirals turning inwards to the vessel. [Peter Hedderwick, "Treatise on Marine Architecture," Edinburgh, 1830]

late 13c., from Old English fiðelere "fiddler" (fem. fiðelestre), agent noun from fiddle (v.). Similar formation in Dutch vedelaar, German Fiedler, Danish fidler. Fiddler's Green "sailor's paradise" first recorded 1825, nautical slang. Fiddler crab is from 1714.

1640s, "holding something in trust," from Latin fiduciarius "entrusted, held in trust," from fiducia "trust, confidence, reliance;" in law, "a deposit, pledge, security," from root of fidere "to trust" (see faith). In Roman law, fiducia was "a right transferred in trust;" paper currency sense (1878) is because its value depends on the trust of the public. As a noun, "one who holds something in trust," from 1630s.

late 13c., possibly from Old French fi, exclamation of disapproval (12c.), and reinforced by Old Norse fy or some other Scandinavian form; it's a general sound of disgust that seems to have developed independently in many languages. Fie-fie was a 19c. British jocular word for "improper," also, as a noun, "woman of tarnished reputation" [OED].

also feoff, 1610s, from French fief (12c.) "a 'feud,' possession, holding, domain; feudal duties, payment," from Medieval Latin feodum "land or other property whose use is granted in return for service," widely said to be from Frankish *fehu-od "payment-estate," or a similar Germanic compound, in which the first element is from Proto-Germanic *fekhu, making it cognate with Old English feoh "money, movable property, cattle" (see fee). Second element perhaps is similar to Old English ead "wealth" (see Edith).

Old English feld "plain, pasture, open land, cultivated land" (as opposed to woodland), also "a parcel of land marked off and used for pasture or tillage," probably related to Old English folde "earth, land," from Proto-Germanic *felthuz "flat land" (Cognates: Old Saxon and Old Frisian feld "field," Old Saxon folda "earth," Middle Dutch velt, Dutch veld Old High German felt, German Feld "field," but not found originally outside West Germanic; Swedish fält, Danish felt are borrowed from German; Finnish pelto "field" is believed to have been adapted from Proto-Germanic). This is from PIE *pel(e)-tu-, from root *pele- (2) "flat, to spread" (see plane (n.1)). The English spelling with -ie- probably is the work of Anglo-French scribes (compare brief, piece).

As "battle-ground," c. 1300. Meaning "sphere or range of any related things" is from mid-14c. Physics sense is from 1845. Collective use for "all engaged in a sport" (or, in horse-racing, all but the favorite) is 1742; play the field "avoid commitment" (1936) is from notion of gamblers betting on other horses than the favorite. Cricket and baseball sense of "ground on which the game is played" is from 1875. Sense of "tract of ground where something is obtained or extracted" is from 1859. As an adjective in Old English combinations, often with a sense of "rural, rustic" (feldcirice "country-church," feldlic "rural"). Of slaves, "assigned to work in the fields" (1817, in field-hand), opposed to house. A field-trial originally was of hunting dogs.

"to go out to fight," 16c., from field (n.) in the specific sense of "battlefield" (Old English). The sports meaning "to stop and return the ball" is first recorded 1823, originally in cricket; figurative sense of this is from 1902. Related: Fielded; fielding.

As spelling suggests, the word originally was the opposite of friend (n.). Both are from the active participles of the Germanic verbs for "to love" and "to hate." According to Bammesberger ["English Etymology"], "The long vowel in FIEND is regular. In FRIEND the vowel has been shortened; perhaps the shortening is due to compounds like FRIENDSHIP, in which the consonant group (-nds-) regularly caused shortening of the preceeding long vowel."

Fiend at first described any hostile enemy (male and female, with abstract noun form feondscipe "fiendship"), but it began to be used in late Old English for "the Devil, Satan" (literally "adversary") as the "enemy of mankind," which shifted its sense to "diabolical person" (early 13c.). The old sense of the word devolved to foe, then to the imported word enemy. For spelling with -ie- see field. Meaning "devotee (of whatever is indicated)," as in dope fiend, is from 1865.